Improved mortising-machine



UNITED STATES PATENT OFFICE.

STEPHEN S. BARTLETT, OF VOONSOOKET, RHODE ISLAND, ASSIGNOR TO HIMSELF AND THOMAS H. DODGE, OF IVASHINGTON, DISTRICT OF COLUMBIA.

Specification forming part of Letters Patent No. 33,330, dated September 24, 1861.

To all whom it may concern.-

Be it known that I, STEPHEN S. BARTLETT, of Woonsocket, in the county of Providence and State of Rhode Island, have invented a new and useful Improvement in Mortising- Machines; and I hereby declare the following to be a true and exact description of the saine, reference being had to the drawings herewith presented, which drawings constitute a part of said description, as follows:

Figure l is a side view of the machine.

A A is the frame.

4l5 B is the bench or table on which the timber is laid to be inortised.

Ois the chisel.

D is a semicircular bracket or piece of metal on which the table rests. It is secured to the front post of the frame (and shown in Fig. 2) by means of the screw-bolts G and E. It may be adjusted higher or lower, and may be placed either in a horizontal or an in- @lined position, so as to cut the lnortise either perpendicularly through the timber or beveled to any angle required.

H H is a head-stock movable on the top ofthe frame, where it fitted to the slide vl t'. It carries the collar K, which forms the fulcrum to the lever L. This collar K is seen at Figs. 3 and 4, (shaded red.) It is supported on centers or pins fr o, its front side notched out so as to admit the top of the swivel S, in order to let the fulcrum be brought directly over the top of the arbor I, which carries the chisel. R R are two small slips of metal to hold down the timber. It may be observed that the spiral spring e (shown at Fig. I) is attached to the rod V, (shaded red,) as also the bent lever U, and the rod NV, which connects it to the head-stock H. This bent lever U has its fulcrum at g, and is connected by the rod V to the treadle T. Thel lever L is put in motion by the shackle-bar Z, which is moved by a crank-pin or stud fixed in the disk F, which is placed on the shaft of the tight and loose pulleys Q. (Shown in Fig. 2.)

X is a stand with a circular slit, placed on the top and front of the frame, and its use is to guide the front end of lever L to prevent its being drawn backward by drawing back the fulcrum. Y is a standard, placed at the for the mortise. Now this machine,when rst started; gives no motion to the chisel at all, by reason ot' the fulcruni of thelever being' right over the arbor I; or, in other Words, the

fulcrum is concentric with the pin which connects the top of the swivel S to the lever. Then by pressing on the treadle T, I draw back the head-stock H. I

The 'connection is shown in Fig. I. The (red-shaded) pitman W connects the stock H to the top arm of the bent lever U, which has its fulcrum at g. Its lower arm is connected by the rod V to the back end of the treadle T. Now by pressing the treadle a little downward a short movement is given to the arbor I, which carries the chisel, and by pressing still lower and lower at each successive stroke the length ot` stroke is increased, while the motion of the lever is all the time give-n by the belt from a power wheel, engine, or drum to pulley Q. Y

I do not claim a shifting fulcrum in a mor` tising-lnachine; but

What I now desire to secure by Letters Patent is- The combination of the stationary slidepiece t', movable sliding fulcrumepiece H,With the frame A, and operating-lever L and spindle I, arranged to operate substantially as and for the purposes set forth.

In testimony whereof I have hereto subscribed my narne in presence ot' two Witnesses.

STEPHEN S. BARTLETT. Vitnesses:

. ABNER JILLSON,

JAMES PIKE. 

